Mark Francis O'Meara (born January 13, 1957) is an American retired professional golfer. He was a tournament winner on the PGA Tour and around the world from the mid-1980s to the late 1990s. He spent nearly 200 weeks in the top-10 of the Official World Golf Ranking from their debut in 1986 to 2000. He won two major championships, the 1998 Masters Tournament and the 1998 Open Championship, becoming the oldest player to win two majors in one year. He was inducted into the World Golf Hall of Fame in 2015.